Control apparatus



Sept. 26, 1939. E Q N Y 2,174,275

CONTROL APPARATUS Filed May 18, 1936 9 INVENTOR Patented Sept. 26, 1939 v 2,174,275

'UNITED STATES PATENT OFFICE CONTROL APPARATUS Estcl C. Raney, Columbus, Ohio, assignor to Ranco Incorporated, a corporation of Ohio Application May 18, 1936, Serial No. 80,293 13 Claims. (Cl. 15&28)

My present invention relates to an electrical apart and spaced in a plane rotated 90 from the system and more particularly to asystem for conplane of the winding 23. It is to be understood trolling burners such as fuel burners. that either set of windings may e til as g In the control of a system for the consumption the starting winding, which would merely cause I of a fuel, it is particularly important to provide rotation in the Opp directioh- As in any adequate means for the ignition of the fuel and squirrel cage induction motor, the rotor or armaalso means to prove or check the ignition of said ture will not start to rotate when the main field fuel. For example, in an oil burner, much fuel is energize t w y equires an additional can be expelled by the jet in a very short period starting winding, or split phase, to throw the 10, of time. -12 this fuel is not immediately ignited. magnetic fi d out of p For t a n.

the flow of the fuel must be completely stopped. when the circuit of the. winding 3 is Closed y It is not only wasteful, but exceedingly dangercomple in the Circuit th u h th 11s 23 and ous to have a combustible mixtur or this ohar- 231, it establishes a magnetic field that is out of acter within the combustion chamber. In the P a e W t the magnetic field 0f the main Windevent of delayed ignition, that is, after several ing 2| and starts the motor to rotate in a clock- 1 minutes have elapsed, it is possible to have a wise direction. The motor will continue to rotate serious explosion. until the circuit of the winding 2 is closed, at One of the objects is to provide a shaded pole which instant the magnetic fi Produced y the motor as a controlling means for the system; this winding 22 is neutralized, in effect, by the mag- 20 'motor is to be actuated by the thermostatic connetic field produced by the winding 24. In other 20 trol, to start and stop the operation of the system words, the two sets of stator windings establish through various switch magnetic fields in opposite directions and since A further object is to provide a commutating the tr n h f he e fields are equal, the motor means or timing device, cooperating with the is stopped. These two windings 22 and 24,there- 25 motor, through a magnetic clutch, to operate the fore, act as an electrical brake on the armature of 25 switches, and mechanical means asso iated with the motor. It is evident that the windings 22 and the commutator for returning it to its originalm be 0 equa ind ct to produce starting position, when di enga d by th lutch, like electrical fields in opposite directions. The Further objects and advantages will be apprinciple of this type of shadedpole motor 20 '30 parent from the following detailed description ay be advantageously utilized to Operate a fuel contained herein: control system as developed in the following de- Fig. 1 is a diagrammatic view of the shaded b npole motor; Referring to Fig. 2, the shaded pole motor is Fig. 2 shows the wiring diagram of th y tem, shown at 20, with its three field windings 2|, 22

' with a schematic view of the commutator in the nd 4. The primary fleld windi 2| is in 35 about the laminated field or core 22; additional, A control device, in th s ca e a thermOstB-t starting position; stant connection with the power line through wire Flg. 3 shows the commutator in the runnin 41 connected to one side of the power line 4| and position; and, through wire 44 to switch 45 which is connected Fig. 4 shows the clutch mechanism and related to the other side of the Power line The Wind- 40 reducing gears. ing 22, being on the same core as winding 2|, is '40 A shaded pole motor is-shown at :0. in which d iv ly upled t th w din II a d a ts, the windings are shown in detail. An armature when its circuit is complete, as a step down transof the squirrel cage type,'is included, to th f former, yielding current at a reduced voltage that with a primary or main stator winding 2| wound is l ed in e controlor auxiliary field windings are provided for startis positioned, remote from the motor", to be acing and stopping the motor; these are also wound tuated by changes in room temperature. The about the core 22. Awinding 22,t6 be termed the starting winding 23 is in series with the room starting winding? comprises two coils 22 and 231 thermostat 25 and a solenoid 21 through the con- 59 that are connected in series. The magnetic fields necting wiring 26, 28, and 29. When the thermoso of these coils are 180' apart and out of phase with stat 25 calls for heat, due to a drop in room temthe magnetic field set up by the main stator wind- D t c os th series circuit. thus Causing ing 2|. An additional winding 24, to be termed energization of the starting winding 22. This the stopping winding, comprises the series conthrows'the magnetic fields of windings 2| and nected coils 24 and 2h. These are also 28 out of phase, wh l the motor 10 t0 66 till ' and Gil supply Till the atomized The closing of the thermostat circuit also energizes the low voltage solenoid ill, which reacts to draw a bar inwardly to engage a gear driven, friction clutch 3i with a movable commutator 32 or timing device, as it may be termed. The clutch 3!! is driven by the motor ill, through a gear attached to the motor shaft and the associated speed reducing gearing indicated at s and 35, said last gear being on the clutch ill. The clutch device, as described, is merely illustrative of one method that may be used to engage the commutator 32 and rotate it at a related speed to the motor The commutator is a rotatable disc having cams 36 and ti, preferably of insulating material, suitably disposed on its periphery. These cams act to open and close associated switches at given time intervals to be described in detail later. A spring is used as a retracting means for the commutator, that is, if the clutch Si is released from the commutator 32 after the commutator has been rotated, the spring will bring the commutator 32 ha is to its original, or starting position, as shown in Fig. 2.

It should be noted that the construction limits the rotation of this commutator or disc to less 360, or a full turn, due to the retracting spring and the action of the associated switches.

in Fig. 2, the commutator is shown in its starting position. hssume'that the thermostat 25 closes the circuit, through the field winding and the solenoid ill, the motor 2@ will start and the solenoid El will he energized draw the bar illl inwardly. This will engage the rotating :iriction clutch ill with the commutator which last will move the cam slowly, in a clockwise direction, to cause closing of a switch 38 that is normally biased to the closed position and held open by the cam in the starting position. The closing of the switch 89 will energize a blower ing ll, 12, switch and wire 63, which in turn mile the other side of newer lin The blower n burner. Simultaneously with the S5 e ntransforiner is ener- 37/, which con motor and pump mechanic ill through the wir is connected to wire '38 switch iii to e ti- 7* ower do, the

p wer. Enerthe av winch causes l g the wires Ell a d [it tomeans for ignition. L

ignition, igni o; incl at the burner. Bur this pi tically :taneors operation, the ommutator co -nues to rotate slowly a clockwise direction. the meantime, the heat from the burner acting upon a control 58,

u which is a thermally operated device. sensitive to temperature changes within t e combustion chamber 6 i. i-ls heat the chamber 66, the switch ti l associated V'Lth the control closes, due to the action of the thermally sensitive control mechanism a id an electrical connection established throur i the stopp .g winding 26 by connected wiring 56 and up to the switch The switch. remains open until it is engagedby the car; 3T on the commutator to complete the circuit. Fig. 3 shows this last position of the commutator earn El and switch The switch E38 may be eliminated, in the preferred form, this swi ch assures 2. tier nite time delay on the sto -g of the commutator and also provides ninnediate bi in the oil? arrears 1 in the position shown in Fig. 3, which is in the normal operating position.

When the room temperature is suficiently high,

. the thermostat 25 acts to break the solenoid circuit, which releases the clutch ill and allows the spring return 38 tov rotate the commutator 32 quickly back to its original position shown in Fig. 2. In this last position, the switch 39 is again opened, breaking the circuit to the blower ll] and the ignition coil ill. This shuts off the burner which allows the control 53 to open its associated switch In other words, the entire system is deenergized, with the exception of winding El, and is again ready to start the heating up cycle.

The control is provided as a safety measure. It the fuel being sprayed by the blower ill does. not ignite, the control 53 will receive no heat and consequently will notclose the switch M. This will allow the motor to continue to rotate, since the stopping winding 2 1 is not energized when switch 58 is closed by stop Ell. Cam Ell, therefore, will continue to rotate until it engages switch it, actuated through lever which is held in place by a spring Gil. As the lever 59 is tripped, the switch G5 opens, breaking the main circuit through the primary field coil 2 i. This, of course, tie-energizes the winding and the series connected solenoid 27 which allows the spring ro turn 38 to bring the commutator back to the original starting positionand stops the operation of the entire system. When this emergency condition arises, the system remains entirely inoper ative by automatic means until the lever is manually reset. The some action occurs when a fuel shortage occurs during a heating cycle.

The fuel control system as described has cer-- tain marked advantages from an operation standpoint. The mechanism is simple. It provides full automatic control for every phase of the cycle of operation as well as providing safety control to dominate any eme" ency condition.

The system as explained need not be limited for use on fluid fuels alone. .it is evident that it could be easily adapted to a coal-fired stolier sysin this event, the ignition device might be eliminated and a safety control, similar to could he placed the bonnet of the furnace to shut he system if the fire was extinguished, th is preventing feeding of coal or coke,

event of fue ortage. nile the form oi .codiment of the present invention as herein disclosed constitutes a pre ferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

I claim:

1. in a fuel control system, in combination with a device to be controlled; of a controller therefor, including a motor. said motor including a plurality of fields; switching mechanism controlled by the motor, one of said fields being adapted to cause rotation of the motor when energized and a second of said fields being adapted to neutralize the first; means responsive to demand for operthe first mentioned field; means responsive to operation of the device and subsequent operation of the motor for completing the circuit of the second mentioned field; and means for returning the switching mechanism to its original position when the circuit is broken by the demand means.

2. In a fuel control system, in combination with a device to be controlled; of a controller therefor, including a switching mechanism, a motor, including a plurality of field windings, for actuating the switching mechanism, one of said windings being normally energized, means for energizing a second winding for starting the motor, means for energizing a third winding to neutralize the effect of the second winding and thereby stop the motor, and mechanically actuated means for returning the switching mechanism to its initial position when the first mentioned winding is deenergized.

3. In a fuel control system, in combination with a device to be controlled; of a controller therefor, including a switching mechanism, a motor, including a plurality of field windings, for actuating the switching mechanism, means for energizing one of said windings to start the motor, means for energizing a second winding to neutralize the effect of the second winding and thereby stop the motor, and mechanically actuated means for returning the switching mechanism to it initial position when the said windings are deener ized.

4. In a fuel control system, in combination with a device to be controlled; of a controller therefor, including a switching mechanism, a motor, a magnetic means to engage said motor to said switching mechanism, said motor having a plurality of field windings, one of said windings being in series with the magneticmeans, control means also in series with the magnetic means for starting the motor and energizing the magnetic means, control means in series with a second-of said windings, said second winding being disposed to neutralize the effect of said first winding and thereby stop the motor and means to return the switching mechanism to its original position in the event the magnetic means is de-energized.

5. In a fuel control system, in combination with a device to be controlled; of a controller therefor, including a switching mechanism, a motor, a magnetic means to engage said motor to said switching mechanism, said motor having a plurality of field windings, one of said windings being in series with the'magnetic means, control means also in series with the magnetic means for starting the motor; and energizing the magnetic means, control means in series with a second of said windings, said second winding being disposed to neutralize the effect of said first winding and thereby stop the motor and means whereby the motor can be stopped and the switching mechanism returned to its original position in the event that the second control means does not close the circuit of the second field winding.

- 6. A control system for translating apparatus,

the combination with mechanism to be controlled, a movable timing device, electrical actuating means for starting movement of the timing device and for starting the mechanism, means operated by the movement of the timing device for rendering the mechanism inoperative and for causing reversal of movement of the timing device, for returning the same to its starting position, said last means being operative after a predetermined operation of the timing device, means responsive to normal operation of the mechanism for rendering inoperative the means for causing reversal and means for rendering the reversal means operative when the first means is rendered ineffective.

7. A control system for a fuel burning device comprising in combination, switching means oper'able for controlling the operation of said device; a timing mechanism operable to actuate the switching means; a control circuit, which when completed, causes the timing mechanism to be rendered operative; a second control circuit for rendering the timing mechanism inoperative when said second control circuit is energized;

. means responsive to the establishment of combustion, and in series with said second control circuit, for partially completing said second circuit; and means operated by the timing mechanism after a predetermined period of operation thereof for completing said second circuit, whereby said timing mechanism is rendered inoperative while said fuel burning device is maintained operative.

8. In a fuel control system, in combination with a device to be controlled; of a controller therefor, including a switching mechanism, a motor, magnetic means for engaging said motor to said switching mechanism, said motor having a plurality of field windings, one of said windings being in series with the magnetic means; control means also in series with the magnetic means for starting the motor and energizing the magnetic means; control means in series with a second of said windings, said second mentioned control means being rendered operative in response to combustion and by operaiton of the said motor a predetermined number of revolutions, said windings being disposed to neutralize the effect of said first winding when the said second mentioned control means is operated and thereby stop the motor.

9. In a fuel control system, in combination with a device to be controlled; a controller therefor, including a shaded pole motor, said motor having a winding which when energized causes the motor to stop; means for energizing the winding; 8. switch for rendering the said device operative; a second switch for energizing the said winding to cause the motor to stop; a. third switch for deenergizing the device, and means actuated by the said motor for operating the switches at time intervals in the order named.

10. In a fuel control system, in combination with a device to be controlled; a controller therefor, including a shaded pole motor, said motor having a winding which when energized causes the motor to stop; means for energizing the winding; a switch for rendering the said device operative; a second switch for energizing the said winding to cause the motor to stop; a third switch for deenergizing the device, and timing means actuated by the said motor for operating the switches at time intervals in the order named, the time interval between the operation of the first mentioned .switch and the said third switch being greater than the time interval between the operation of the said second switch and the third switch.

11. In .a fuel control system, in combination with aidevice to be controlled, of a controller therefor, including a motor, said motor having a plurality of fields, one of said fields being adapted to cause rotation of the motor, when energized, for initiating operation of the device, and a second of said fields being adapted, when enersized, to neutralize the said one field to stop the motor; means for energizing the said second winding including switching means: in the field meme, said switching means being evdepfied to ellose in response to predetermined number of revolutions of me motor emf; ineesponse to 5; mm bmtioe oonou tioe produced by operation the @evioe. 1233.. In a fuel eontbz'oi system, on combination we a device to be cont-roiled; eeontrollee there-= foe including a switch for eneegfieine the device when the switch is closed, end switch ele= emergfizlmg the device; means ieeludine emovebfie member for operating the said smtehes, one of we switches being operated when the member moves to a predetermined position and the other of said ewitches being operefied when the movable memloee moves Go a second predetermmed posi worm; and I" ems for stopping the movable mem= Teen at o e ereeetelmmed eosition m respom to a; groomed by opemtioe of the de- Vice and; mov the mo able memi .v amem to emerge on of we de- 1 o e the mefiioneel means :mhse- 15 

